Theorem wpthswwlks2on 30054

Description: For two different vertices, a walk of length 2 between these vertices is a simple path of length 2 between these vertices in a simple graph. (Contributed by Alexander van der Vekens, 2-Mar-2018.) (Revised by AV, 16-Mar-2022.) (Revised by Ender Ting, 29-Jan-2026.)

Assertion

Ref	Expression
wpthswwlks2on	⊢ ((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) → (𝐴(2 WSPathsNOn 𝐺)𝐵) = (𝐴(2 WWalksNOn 𝐺)𝐵))

Proof of Theorem wpthswwlks2on

Dummy variables 𝑓 𝑤 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		wwlknon 29947	. . . . . . 7 ⊢ (𝑤 ∈ (𝐴(2 WWalksNOn 𝐺)𝐵) ↔ (𝑤 ∈ (2 WWalksN 𝐺) ∧ (𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵))
2	1	a1i 11	. . . . . 6 ⊢ ((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) → (𝑤 ∈ (𝐴(2 WWalksNOn 𝐺)𝐵) ↔ (𝑤 ∈ (2 WWalksN 𝐺) ∧ (𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)))
3	2	anbi1d 638	. . . . 5 ⊢ ((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) → ((𝑤 ∈ (𝐴(2 WWalksNOn 𝐺)𝐵) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤) ↔ ((𝑤 ∈ (2 WWalksN 𝐺) ∧ (𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤)))
4		3anass 1101	. . . . . . 7 ⊢ ((𝑤 ∈ (2 WWalksN 𝐺) ∧ (𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) ↔ (𝑤 ∈ (2 WWalksN 𝐺) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)))
5	4	anbi1i 631	. . . . . 6 ⊢ (((𝑤 ∈ (2 WWalksN 𝐺) ∧ (𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤) ↔ ((𝑤 ∈ (2 WWalksN 𝐺) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤))
6		anass 470	. . . . . 6 ⊢ (((𝑤 ∈ (2 WWalksN 𝐺) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤) ↔ (𝑤 ∈ (2 WWalksN 𝐺) ∧ (((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤)))
7	5, 6	bitri 277	. . . . 5 ⊢ (((𝑤 ∈ (2 WWalksN 𝐺) ∧ (𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤) ↔ (𝑤 ∈ (2 WWalksN 𝐺) ∧ (((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤)))
8	3, 7	bitrdi 289	. . . 4 ⊢ ((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) → ((𝑤 ∈ (𝐴(2 WWalksNOn 𝐺)𝐵) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤) ↔ (𝑤 ∈ (2 WWalksN 𝐺) ∧ (((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤))))
9	8	rabbidva2 3395	. . 3 ⊢ ((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) → {𝑤 ∈ (𝐴(2 WWalksNOn 𝐺)𝐵) ∣ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤} = {𝑤 ∈ (2 WWalksN 𝐺) ∣ (((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤)})
10		usgruspgr 29271	. . . . . . . . . . 11 ⊢ (𝐺 ∈ USGraph → 𝐺 ∈ USPGraph)
11		wlklnwwlkn 29974	. . . . . . . . . . 11 ⊢ (𝐺 ∈ USPGraph → (∃𝑓(𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2) ↔ 𝑤 ∈ (2 WWalksN 𝐺)))
12	10, 11	syl 17	. . . . . . . . . 10 ⊢ (𝐺 ∈ USGraph → (∃𝑓(𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2) ↔ 𝑤 ∈ (2 WWalksN 𝐺)))
13	12	bicomd 225	. . . . . . . . 9 ⊢ (𝐺 ∈ USGraph → (𝑤 ∈ (2 WWalksN 𝐺) ↔ ∃𝑓(𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)))
14	13	adantr 482	. . . . . . . 8 ⊢ ((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) → (𝑤 ∈ (2 WWalksN 𝐺) ↔ ∃𝑓(𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)))
15		simprl 777	. . . . . . . . . . . . . 14 ⊢ ((((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ (𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)) → 𝑓(Walks‘𝐺)𝑤)
16		simprl 777	. . . . . . . . . . . . . . 15 ⊢ (((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) → (𝑤‘0) = 𝐴)
17	16	adantr 482	. . . . . . . . . . . . . 14 ⊢ ((((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ (𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)) → (𝑤‘0) = 𝐴)
18		fveq2 6831	. . . . . . . . . . . . . . . 16 ⊢ ((♯‘𝑓) = 2 → (𝑤‘(♯‘𝑓)) = (𝑤‘2))
19	18	ad2antll 736	. . . . . . . . . . . . . . 15 ⊢ ((((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ (𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)) → (𝑤‘(♯‘𝑓)) = (𝑤‘2))
20		simprr 779	. . . . . . . . . . . . . . . 16 ⊢ (((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) → (𝑤‘2) = 𝐵)
21	20	adantr 482	. . . . . . . . . . . . . . 15 ⊢ ((((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ (𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)) → (𝑤‘2) = 𝐵)
22	19, 21	eqtrd 2776	. . . . . . . . . . . . . 14 ⊢ ((((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ (𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)) → (𝑤‘(♯‘𝑓)) = 𝐵)
23		eqid 2741	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ (Vtx‘𝐺) = (Vtx‘𝐺)
24	23	wlkp 29707	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝑓(Walks‘𝐺)𝑤 → 𝑤:(0...(♯‘𝑓))⟶(Vtx‘𝐺))
25		oveq2 7368	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ((♯‘𝑓) = 2 → (0...(♯‘𝑓)) = (0...2))
26	25	feq2d 6643	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((♯‘𝑓) = 2 → (𝑤:(0...(♯‘𝑓))⟶(Vtx‘𝐺) ↔ 𝑤:(0...2)⟶(Vtx‘𝐺)))
27	24, 26	syl5ibcom 247	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑓(Walks‘𝐺)𝑤 → ((♯‘𝑓) = 2 → 𝑤:(0...2)⟶(Vtx‘𝐺)))
28	27	imp 408	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2) → 𝑤:(0...2)⟶(Vtx‘𝐺))
29		id 22	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝑤:(0...2)⟶(Vtx‘𝐺) → 𝑤:(0...2)⟶(Vtx‘𝐺))
30		2nn0 12449	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ 2 ∈ ℕ0
31		0elfz 13573	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ (2 ∈ ℕ0 → 0 ∈ (0...2))
32	30, 31	mp1i 13	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝑤:(0...2)⟶(Vtx‘𝐺) → 0 ∈ (0...2))
33	29, 32	ffvelcdmd 7030	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑤:(0...2)⟶(Vtx‘𝐺) → (𝑤‘0) ∈ (Vtx‘𝐺))
34		nn0fz0 13574	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (2 ∈ ℕ0 ↔ 2 ∈ (0...2))
35	30, 34	mpbi 232	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ 2 ∈ (0...2)
36	35	a1i 11	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝑤:(0...2)⟶(Vtx‘𝐺) → 2 ∈ (0...2))
37	29, 36	ffvelcdmd 7030	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑤:(0...2)⟶(Vtx‘𝐺) → (𝑤‘2) ∈ (Vtx‘𝐺))
38	33, 37	jca 517	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑤:(0...2)⟶(Vtx‘𝐺) → ((𝑤‘0) ∈ (Vtx‘𝐺) ∧ (𝑤‘2) ∈ (Vtx‘𝐺)))
39	28, 38	syl 17	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2) → ((𝑤‘0) ∈ (Vtx‘𝐺) ∧ (𝑤‘2) ∈ (Vtx‘𝐺)))
40		eleq1 2829	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝑤‘0) = 𝐴 → ((𝑤‘0) ∈ (Vtx‘𝐺) ↔ 𝐴 ∈ (Vtx‘𝐺)))
41		eleq1 2829	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝑤‘2) = 𝐵 → ((𝑤‘2) ∈ (Vtx‘𝐺) ↔ 𝐵 ∈ (Vtx‘𝐺)))
42	40, 41	bi2anan9 645	. . . . . . . . . . . . . . . . . 18 ⊢ (((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) → (((𝑤‘0) ∈ (Vtx‘𝐺) ∧ (𝑤‘2) ∈ (Vtx‘𝐺)) ↔ (𝐴 ∈ (Vtx‘𝐺) ∧ 𝐵 ∈ (Vtx‘𝐺))))
43	39, 42	imbitrid 246	. . . . . . . . . . . . . . . . 17 ⊢ (((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) → ((𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2) → (𝐴 ∈ (Vtx‘𝐺) ∧ 𝐵 ∈ (Vtx‘𝐺))))
44	43	adantl 483	. . . . . . . . . . . . . . . 16 ⊢ (((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) → ((𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2) → (𝐴 ∈ (Vtx‘𝐺) ∧ 𝐵 ∈ (Vtx‘𝐺))))
45	44	imp 408	. . . . . . . . . . . . . . 15 ⊢ ((((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ (𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)) → (𝐴 ∈ (Vtx‘𝐺) ∧ 𝐵 ∈ (Vtx‘𝐺)))
46		vex 3437	. . . . . . . . . . . . . . . 16 ⊢ 𝑓 ∈ V
47		vex 3437	. . . . . . . . . . . . . . . 16 ⊢ 𝑤 ∈ V
48	46, 47	pm3.2i 472	. . . . . . . . . . . . . . 15 ⊢ (𝑓 ∈ V ∧ 𝑤 ∈ V)
49	23	iswlkon 29746	. . . . . . . . . . . . . . 15 ⊢ (((𝐴 ∈ (Vtx‘𝐺) ∧ 𝐵 ∈ (Vtx‘𝐺)) ∧ (𝑓 ∈ V ∧ 𝑤 ∈ V)) → (𝑓(𝐴(WalksOn‘𝐺)𝐵)𝑤 ↔ (𝑓(Walks‘𝐺)𝑤 ∧ (𝑤‘0) = 𝐴 ∧ (𝑤‘(♯‘𝑓)) = 𝐵)))
50	45, 48, 49	sylancl 593	. . . . . . . . . . . . . 14 ⊢ ((((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ (𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)) → (𝑓(𝐴(WalksOn‘𝐺)𝐵)𝑤 ↔ (𝑓(Walks‘𝐺)𝑤 ∧ (𝑤‘0) = 𝐴 ∧ (𝑤‘(♯‘𝑓)) = 𝐵)))
51	15, 17, 22, 50	mpbir3and 1350	. . . . . . . . . . . . 13 ⊢ ((((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ (𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)) → 𝑓(𝐴(WalksOn‘𝐺)𝐵)𝑤)
52		simplll 781	. . . . . . . . . . . . . 14 ⊢ ((((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ (𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)) → 𝐺 ∈ USGraph)
53		simprr 779	. . . . . . . . . . . . . 14 ⊢ ((((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ (𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)) → (♯‘𝑓) = 2)
54		simpllr 782	. . . . . . . . . . . . . 14 ⊢ ((((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ (𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)) → 𝐴 ≠ 𝐵)
55		usgr2wlkspth 29849	. . . . . . . . . . . . . 14 ⊢ ((𝐺 ∈ USGraph ∧ (♯‘𝑓) = 2 ∧ 𝐴 ≠ 𝐵) → (𝑓(𝐴(WalksOn‘𝐺)𝐵)𝑤 ↔ 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤))
56	52, 53, 54, 55	syl3anc 1380	. . . . . . . . . . . . 13 ⊢ ((((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ (𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)) → (𝑓(𝐴(WalksOn‘𝐺)𝐵)𝑤 ↔ 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤))
57	51, 56	mpbid 234	. . . . . . . . . . . 12 ⊢ ((((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) ∧ (𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2)) → 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤)
58	57	ex 414	. . . . . . . . . . 11 ⊢ (((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) → ((𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2) → 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤))
59	58	eximdv 1925	. . . . . . . . . 10 ⊢ (((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)) → (∃𝑓(𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2) → ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤))
60	59	ex 414	. . . . . . . . 9 ⊢ ((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) → (((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) → (∃𝑓(𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2) → ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤)))
61	60	com23 86	. . . . . . . 8 ⊢ ((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) → (∃𝑓(𝑓(Walks‘𝐺)𝑤 ∧ (♯‘𝑓) = 2) → (((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) → ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤)))
62	14, 61	sylbid 242	. . . . . . 7 ⊢ ((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) → (𝑤 ∈ (2 WWalksN 𝐺) → (((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) → ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤)))
63	62	imp 408	. . . . . 6 ⊢ (((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ 𝑤 ∈ (2 WWalksN 𝐺)) → (((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) → ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤))
64	63	pm4.71d 567	. . . . 5 ⊢ (((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ 𝑤 ∈ (2 WWalksN 𝐺)) → (((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) ↔ (((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤)))
65	64	bicomd 225	. . . 4 ⊢ (((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) ∧ 𝑤 ∈ (2 WWalksN 𝐺)) → ((((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤) ↔ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)))
66	65	rabbidva 3399	. . 3 ⊢ ((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) → {𝑤 ∈ (2 WWalksN 𝐺) ∣ (((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵) ∧ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤)} = {𝑤 ∈ (2 WWalksN 𝐺) ∣ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)})
67	9, 66	eqtrd 2776	. 2 ⊢ ((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) → {𝑤 ∈ (𝐴(2 WWalksNOn 𝐺)𝐵) ∣ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤} = {𝑤 ∈ (2 WWalksN 𝐺) ∣ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)})
68	23	iswspthsnon 29946	. 2 ⊢ (𝐴(2 WSPathsNOn 𝐺)𝐵) = {𝑤 ∈ (𝐴(2 WWalksNOn 𝐺)𝐵) ∣ ∃𝑓 𝑓(𝐴(SPathsOn‘𝐺)𝐵)𝑤}
69	23	iswwlksnon 29943	. 2 ⊢ (𝐴(2 WWalksNOn 𝐺)𝐵) = {𝑤 ∈ (2 WWalksN 𝐺) ∣ ((𝑤‘0) = 𝐴 ∧ (𝑤‘2) = 𝐵)}
70	67, 68, 69	3eqtr4g 2801	1 ⊢ ((𝐺 ∈ USGraph ∧ 𝐴 ≠ 𝐵) → (𝐴(2 WSPathsNOn 𝐺)𝐵) = (𝐴(2 WWalksNOn 𝐺)𝐵))

Syntax hints:   → wi 4   ↔ wb 208   ∧ wa 397   ∧ w3a 1093   = wceq 1548  ∃wex 1787   ∈ wcel 2121   ≠ wne 2936  {crab 3393  Vcvv 3433   class class class wbr 5075  ⟶wf 6485  ‘cfv 6489  (class class class)co 7360  0cc0 11033  2c2 12231  ℕ₀cn0 12432  ...cfz 13456  ♯chash 14287  Vtxcvtx 29087  USPGraphcuspgr 29239  USGraphcusgr 29240  Walkscwlks 29687  WalksOncwlkson 29688  SPathsOncspthson 29803   WWalksN cwwlksn 29916   WWalksNOn cwwlksnon 29917   WSPathsNOn cwwspthsnon 29919

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1803  ax-4 1817  ax-5 1918  ax-6 1975  ax-7 2016  ax-8 2123  ax-9 2131  ax-10 2154  ax-11 2170  ax-12 2191  ax-ext 2713  ax-rep 5202  ax-sep 5221  ax-nul 5231  ax-pow 5297  ax-pr 5365  ax-un 7682  ax-cnex 11089  ax-resscn 11090  ax-1cn 11091  ax-icn 11092  ax-addcl 11093  ax-addrcl 11094  ax-mulcl 11095  ax-mulrcl 11096  ax-mulcom 11097  ax-addass 11098  ax-mulass 11099  ax-distr 11100  ax-i2m1 11101  ax-1ne0 11102  ax-1rid 11103  ax-rnegex 11104  ax-rrecex 11105  ax-cnre 11106  ax-pre-lttri 11107  ax-pre-lttrn 11108  ax-pre-ltadd 11109  ax-pre-mulgt0 11110

This theorem depends on definitions:  df-bi 209  df-an 398  df-or 855  df-ifp 1070  df-3or 1094  df-3an 1095  df-tru 1551  df-fal 1561  df-ex 1788  df-nf 1792  df-sb 2075  df-mo 2545  df-eu 2575  df-clab 2720  df-cleq 2733  df-clel 2816  df-nfc 2890  df-ne 2937  df-nel 3041  df-ral 3056  df-rex 3066  df-reu 3347  df-rab 3394  df-v 3435  df-sbc 3726  df-csb 3834  df-dif 3888  df-un 3890  df-in 3892  df-ss 3902  df-pss 3905  df-nul 4265  df-if 4458  df-pw 4534  df-sn 4559  df-pr 4561  df-tp 4563  df-op 4565  df-uni 4842  df-int 4881  df-iun 4926  df-br 5076  df-opab 5138  df-mpt 5157  df-tr 5183  df-id 5516  df-eprel 5521  df-po 5529  df-so 5530  df-fr 5574  df-we 5576  df-xp 5627  df-rel 5628  df-cnv 5629  df-co 5630  df-dm 5631  df-rn 5632  df-res 5633  df-ima 5634  df-pred 6256  df-ord 6317  df-on 6318  df-lim 6319  df-suc 6320  df-iota 6445  df-fun 6491  df-fn 6492  df-f 6493  df-f1 6494  df-fo 6495  df-f1o 6496  df-fv 6497  df-riota 7317  df-ov 7363  df-oprab 7364  df-mpo 7365  df-om 7811  df-1st 7935  df-2nd 7936  df-frecs 8225  df-wrecs 8256  df-recs 8305  df-rdg 8343  df-1o 8399  df-2o 8400  df-oadd 8403  df-er 8637  df-map 8769  df-pm 8770  df-en 8888  df-dom 8889  df-sdom 8890  df-fin 8891  df-dju 9820  df-card 9858  df-pnf 11176  df-mnf 11177  df-xr 11178  df-ltxr 11179  df-le 11180  df-sub 11374  df-neg 11375  df-nn 12170  df-2 12239  df-3 12240  df-n0 12433  df-xnn0 12506  df-z 12520  df-uz 12784  df-fz 13457  df-fzo 13604  df-hash 14288  df-word 14471  df-concat 14528  df-s1 14554  df-s2 14805  df-s3 14806  df-edg 29139  df-uhgr 29149  df-upgr 29173  df-umgr 29174  df-uspgr 29241  df-usgr 29242  df-wlks 29690  df-wlkson 29691  df-trls 29781  df-trlson 29782  df-pths 29804  df-spths 29805  df-pthson 29806  df-spthson 29807  df-wwlks 29920  df-wwlksn 29921  df-wwlksnon 29922  df-wspthsnon 29924

This theorem is referenced by:  usgr2wspthons3  30057  frgr2wsp1  30422